Biodiesel Productions from Vegetable Oils Using Heterogeneous Catalysts and Their Applications as Lubricity Additives

Fatty acid methyl esters (FAME) are produced by transesterification of vegetable oil with methanol usually in presence of an alkaline catalyst. The purpose of this work is to compare the performance of heterogeneous (CaO, MgO, Ba(OH)2, Li/CaO, Zeolite) and homogeneous (KOH) catalyst for the transesterification of vegetable oil. The effect of stirring speed and addition of ethanol with methanol on ester yield was studied. This research showed that stirring speed has substantial effect on the ester yield both in homogeneous and heterogeneous catalyzed reaction. Addition of ethanol with methanol has improved the rate of formation of ester, thus helped in reducing the mass transfer limitations. Amongst all the heterogeneous catalysts examined, the performance of Ba(OH)2 catalyst was better which produced 99 wt% ester yield in 480 min and its performance was comparable to that of potassium hydroxide. Ester obtained from canola oil and methanol and ethanol mixture (3:3) {MEE (3:3)} acted as a good lubricity additive by reducing wear scar area by 16% and improving the lubricity number of base fuel by 20%.